The best test for COPD is a lung function test called spirometry. This involves blowing out as hard as possible into a small machine that tests lung capacity. The results can be checked right away, and the test does not involve exercising, drawing blood, or exposure to radiation.

Using a stethoscope to listen to the lungs can also be helpful. However, sometimes the lungs sound normal even when COPD is present.

Pictures of the lungs (such as x-rays and CT scans) can be helpful, but sometimes look normal even when a person has COPD (especially chest x-ray).

Sometimes patients need to have a blood test (called arterial blood gas) to measure the amounts of oxygen and carbon dioxide in the blood.

COPD is a long-term (chronic) illness. The disease will get worse more quickly if you do not stop smoking.

Patients with severe COPD will be short of breath with most activities and will be admitted to the hospital more often. These patients should talk with their doctor about breathing machines and end-of-life care.

Not smoking prevents most COPD. Ask your doctor or health care provider about quit-smoking programs. Medicines are also available to help kick the smoking habit. The medicines are most effective if you are motivated to quit.

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